Sari , S., and G. D. Yuliana. “Electronic Word of Mouth Melalui Youtube: Studi Terhadap Beauty Vlogger Kosmetik Wardah ”. CoverAge: Journal of Strategic Communication, Vol. 8, no. 1, Sept. 2017, pp. 61-69, http://journal.univpancasila.ac.id/index.php/coverage/article/view/583.